Winding device

ABSTRACT

A winding device includes a winding member that rotates to wind a flexible member therearound, a first rotating member that is rotatable, a second rotating member that is rotatable coaxially with the winding member and has a smaller resistance to rotation in a predetermined direction than that to rotation in a direction opposite the predetermined direction, and an engaging member. When the first rotating member is subjected to a first torque, the engaging member brings the winding member, the first rotating member, and the second rotating member into engagement with one another, so that the winding member becomes rotatable together with the first rotating member in the predetermined direction. When the first rotating member is subjected to a second torque in a direction opposite that of the first torque, the engaging member releases the engagement, so that the winding member becomes rotatable in the direction opposite the predetermined direction.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a winding device for winding a flexible member.

2. Description of the Related Art

A head-mounted display (HMD) is well known as a display apparatus of head-mounted type. The HMD is widely used because it allows easy viewing of images on a large screen, facilitates viewing of stereoscopic images, and is movable with the user. Well known examples of a mounting mechanism for mounting the HMD include one in which a belt-like flexible member is fastened around the head, and another having a front-head pressing member and a back-head pressing member. In the latter example, the HMD is mounted or removed by moving the back-head pressing member back and forth to fasten or loosen the HMD on the head. Japanese Patent Laid-Open No. 7-333547 discloses a mounting mechanism using a wire. The disclosed mounting mechanism allows the operator to easily mount the HMD while holding the HMD with one hand.

A winding mechanism disclosed in Japanese Patent Laid-Open No. 7-333547 has a structure in which pulling force of a spring causes a ratchet pawl to detent-engage and lock ratchet teeth of a ratchet wheel, so that a wound linear member is prevented from being unwound. It is thus difficult to control backward movement of the linear member at positions other than locking positions between the ratchet pawl and the ratchet teeth. If the operator is unable to stop winding at desired positions, the HMD may be uncomfortable to wear. To solve this problem, it may be possible to increase the number of ratchet teeth so as to allow finer engagement and locking. However, a larger number of ratchet teeth usually require a ratchet wheel having a larger diameter. This is disadvantageous for the HMD which is desired to be compact and lightweight. Alternatively, a one-way mechanism, such as a one-way clutch, may be used as a winding mechanism. The one-way mechanism has a plurality of built-in rollers and allows rotation in only one direction. The one-way mechanism allows the operator to stop winding by stopping rotation at a desired position. However, this makes it complicated to release locking of backward rotation.

SUMMARY OF THE INVENTION

The present invention has been made in consideration of the above situation. The present invention provides improved operational feeling of a wiring device with a simple configuration.

According to an aspect of the present invention, a winding device includes a winding member configured to rotate to wind a flexible member therearound; a first rotating member configured to be rotatable; a second rotating member configured to be rotatable coaxially with the winding member, and having a smaller resistance to rotation in a predetermined direction than that to rotation in a direction opposite the predetermined direction; and an engaging member. When the first rotating member is subjected to a first torque, the engaging member brings the winding member, the first rotating member, and the second rotating member into engagement with one another, so that the winding member becomes rotatable together with the first rotating member in the predetermined direction. When the first rotating member is subjected to a second torque in a direction opposite that of the first torque, the engaging member releases the engagement, so that the winding member becomes rotatable in the direction opposite the predetermined direction.

Other features and advantages of the present invention will be apparent from the following description taken in conjunction with the accompanying drawings, in which like reference characters designate the same or similar parts throughout the figures thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

FIG. 1 is an external view of an HMD according to an embodiment of the present invention.

FIG. 2 illustrates the HMD of FIG. 1 as viewed from the top of the wearer's head.

FIG. 3 illustrates the HMD of FIG. 1 as viewed from a side of the wearer's head.

FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3 to illustrate a structure of an adjusting unit.

FIG. 5 is a cross-sectional view taken along line V-V of FIG. 2 to illustrate a structure of the adjusting unit.

FIG. 6 illustrates an operation of the adjusting unit during a winding operation.

FIG. 7 illustrates a state in which wedge members are in contact with a pulley.

FIG. 8 is a cross-sectional view taken along line V-V of FIG. 2 to illustrate a structure of the adjusting unit having alternative components.

FIG. 9 is a perspective view of a ski boot provided with the adjusting unit.

FIG. 10 is a side view of the ski boot provided with the adjusting unit.

DESCRIPTION OF THE EMBODIMENTS

Exemplary embodiments of the present invention will be described in detail in accordance with the accompanying drawings.

FIG. 1 is an external view of an HMD according to a first embodiment of the present invention. When wearing the HMD on the head, the wearer can observe images displayed by the HMD.

A display unit 101 receives an image signal from a personal computer (PC) or the like, and displays an image to the wearer wearing the HMD. The display unit 101 includes a display device, such as a charge-coupled device (CCD) sensor, for displaying an image, and an optical system. The optical system enlarges an image on the display device, and guides the enlarged image to the eyes of the wearer wearing the HMD.

A frame 102 covers the top and sides of the wearer's head. The frame 102 hangs across the top of the wearer's head to cover both sides of the head. The frame 102 is connected to the display unit 101.

A tube 103 extends around the back of the wearer's head. The tube 103 is an elastic accordion tube connected and secured to the frame 102.

A back head pad 104 comes into contact with the back of the wearer's head. The back head pad 104 is connected and secured to the tube 103.

A front head pad 105 comes into contact with the front of the wearer's head. The front head pad 105 is connected and secured to the display unit 101.

A top head pad 106 comes into contact with the top of the wearer's head. As described above, the back head pad 104, the front head pad 105, and the top head pad 106 serve as mounting members which allow the wearer to wear the HMD on his/her head.

A wire 107 is placed such that it passes internally through the tube 103, the frame 102, and the top head pad 106. The wire 107 extends through a hole 108 in the frame 102 to the outside of the frame 102, and passes internally through the top head pad 106. As described above, the wire 107 serves as a wire member.

An adjusting unit 109 is used to adjust the tension of the wire 107. Rotating the adjusting unit 109 allows adjustment of the tension of the wire 107. A configuration of the adjusting unit 109 will be described in detail below. An end of the wire 107 is connected to point A of the adjusting unit 109 such that the wire 107 is movable about the adjusting unit 109, while the other end of the wire 107 is connected to point B inside the frame 102.

A guiding member 110 is connected to the frame 102 and guides movement of the top head pad 106. The top head pad 106 is moved by the tension of the wire 107. The top head pad 106 is guided by the guiding member 110 to move in a direction perpendicular to the wearer's head.

A leaf spring 111 is fastened to the top of the frame 102 with screws or the like at one end, and fastened to the back head pad 104 with screws or the like at the other end. The leaf spring 111 biases the back head pad 104 in the direction of arrow P.

FIG. 2 illustrates the HMD of FIG. 1 as viewed from the top of the wearer's head. The configuration of each component is the same as that illustrated in FIG. 1. A cross-sectional view taken along line V-V of FIG. 2 is given in FIG. 5 to describe an internal structure of the adjusting unit 109.

FIG. 3 illustrates the HMD of FIG. 1 as viewed from a side of the wearer's head. The configuration of each component is the same as that illustrated in FIG. 1. A cross-sectional view taken along line IV-IV of FIG. 3 is given in FIG. 4 to describe an internal structure of the adjusting unit 109.

The HMD according to the first embodiment is configured as described above. The wearer rotates the adjusting unit 109 to wind the wire 107. When the wire 107 is wound, the back head pad 104 and top head pad 106 connected to the wire 107 are moved in a direction to fasten the HMD to the wearer's head. That is, by rotating the adjusting unit 109, the HMD is secured to the wearer's head. The back head pad 104 and top head pad 106 fastened to the wearer's head can be loosened by rotating the adjusting unit 109 backward. Next, a structure of the adjusting unit 109 according to the first embodiment will be described in detail.

FIG. 4 is a cross-sectional view taken along line IV-IV of FIG. 3 to illustrate a structure of the adjusting unit 109.

FIG. 5 is a cross-sectional view taken along line V-V of FIG. 2 to illustrate a structure of the adjusting unit 109. Hereinafter, a structure of the adjusting unit 109 will be described with reference to FIG. 4 and FIG. 5.

An adjusting dial 401 is rotated manually by the wearer. The adjusting dial 401 serves as a first rotating member that is rotatable. It is desirable that the adjusting dial 401 be cylindrical in shape.

A support shaft 402 is disposed on the axis of rotation of the adjusting dial 401. The support shaft 402 has a screw 403 at one end, and is fastened to the frame 102 with a nut 404.

A one-way clutch 405 is on the support shaft 402. The one-way clutch 405 is rotatable only in a predetermined direction about the support shaft 402. In the first embodiment, the one-way clutch 405 is rotatable only in a clockwise direction in FIG. 5. The one-way clutch 405 has a structure based on publicly known technology, and thus will not be described here.

A polygonal piece 406 is press-fitted to the outer periphery of the one-way clutch 405. The polygonal piece 406 is thus rotatable only in the clockwise direction in FIG. 5, and is not rotatable in a counterclockwise direction opposite the clockwise direction. As illustrated in FIG. 5, the polygonal piece 406 has a polygonal contour. Each side of the polygon has a groove 407. The polygonal piece 406 press-fitted to the outer periphery of the one-way clutch 405 serves as a second rotating member having a greater resistance to rotation in directions other than a predetermined direction.

A pulley 408 winds the wire 107 therearound to adjust tension applied to the wire 107. An end of the wire 107 is connected to the pulley 408. The pulley 408 rotates about the support shaft 402 to wind the wire 107 therearound. The pulley 408 rotates coaxially with the polygonal piece 406. In the first embodiment, the pulley 408 rotates clockwise in FIG. 5 to wind the wire 107 therearound, and rotates counterclockwise to loosen the wire 107. As described above, the pulley 408 serves as a winding member capable of winding the wire 107 therearound.

A plurality of wedge members 409 is disposed between the polygonal piece 406 and the pulley 408. Each of the wedge members 409 has a protrusion 410, which is fitted in the corresponding groove 407. Each wedge member 409 serves as an engaging member having a wedge shape.

A plurality of boss members 411 is connected to the adjusting dial 401. As illustrated in FIG. 5, more than one of the plurality of boss members 411 are arranged to come into contact with the corresponding wedge member 409.

As described above, the boss members 411 are connected to the adjusting dial 401. Therefore, when the wearer rotates the adjusting dial 401, the torque is transmitted through the boss members 411 to the wedge members 409.

A biasing member 412 is provided for each groove 407. The biasing member 412, such as a spring, is in contact with the corresponding protrusion 410, and thus biases the corresponding wedge member 409 clockwise. Next, an operation for mounting the HMD using the adjusting unit 109 will be described in detail.

First, the wearer places the HMD on the head, holds the frame 102 with the left hand, and holds the adjusting unit 109 with the right hand. Next, the front of the wearer's head is fitted to the front head pad 105. Then, by rotating the adjusting unit 109 clockwise, the back head pad 104 and the top head pad 106 are fastened to the wearer's head.

FIG. 6 illustrates an operation of the adjusting unit 109 during a winding operation. First, when the wearer rotates the adjusting dial 401 of the adjusting unit 109 clockwise, the boss members 411 connected to the adjusting dial 401 are moved clockwise. The boss members 411 come into contact with the corresponding wedge members 409 to move the wedge members 409 clockwise about the support shaft 402. Since the polygonal piece 406 has a polygonal shape, a gap between the polygonal piece 406 and the pulley 408 is reduced at a position near each vertex of the polygon. Therefore, when the wedge members 409 continue moving, each of the wedge members 409 is inserted into the gap between the polygonal piece 406 and the pulley 408 at a position where the gap is reduced. When the wedge members 409 are inserted into the gap, the adjusting dial 401, the polygonal piece 406, and the pulley 408 are brought into engagement with one another through the wedge members 409. The engagement allows the rotation of the adjusting dial 401 to be transmitted to the polygonal piece 406 and the pulley 408. This means that if the adjusting dial 401 is rotated clockwise, the polygonal piece 406 and the pulley 408 are also rotated clockwise. Therefore, if the wearer rotates the adjusting dial 401 clockwise after the engagement, the pulley 408 winds the wire 107 therearound, and thus the back head pad 104 and the top head pad 106 can be fastened to the wearer's head.

After completion of the fastening operation, the wound wire 107 is under tension caused by a load applied thereto by the leaf spring 111. At the same time, the pulley 408 is subjected to a load in the counterclockwise direction. Since the pulley 408 engages with the adjusting dial 401 and the polygonal piece 406, the adjusting dial 401 and the polygonal piece 406 are also subjected to a load in the counterclockwise direction. However, since the polygonal piece 406 is press-fitted to the outer periphery of the one-way clutch 405 that rotates only clockwise, the polygonal piece 406 does not rotate counterclockwise. This means that the adjusting dial 401 and the pulley 408 that engage with the polygonal piece 406 do not rotate counterclockwise. Therefore, even when the wearer moves his/her hand off the adjusting dial 401 after completion of the fastening, it is possible to keep the back head pad 104 and the top head pad 106 fastened. Thus, as described above, the wearer can fasten the HMD to his/her head and keep the HMD fastened as desired.

Next, an operation performed to release fastening will be described. To release fastening, the wearer rotates the adjusting dial 401 counterclockwise. This causes the boss members 411 connected to the adjusting dial 401 to move counterclockwise. When the boss members 411 come into contact with the corresponding wedge members 409, a load is applied to the wedge members 409 in the counterclockwise direction. When the load applied to the wedge members 409 by the boss members 411 exceeds friction of the wedge members 409 with the polygonal piece 406 and the pulley 408, the wedge members 409 are moved out of the gap between the polygonal piece 406 and the pulley 408. This releases the engagement between the polygonal piece 406 and the pulley 408. Then, the pulley 408 becomes rotatable counterclockwise. As described above, the wound wire 107 is under tension caused by a load applied thereto by the leaf spring 111. After the engagement is released, however, the pulley 408 rotates counterclockwise to loosen the wound wire 107. After the engagement is released, if the wearer further rotates the adjusting dial 401 counterclockwise by an amount greater than a predetermined amount, the wedge members 409 are inserted into narrow portions of the gap between the polygonal piece 406 and the pulley 408, and brought into contact with the pulley 408.

FIG. 7 illustrates a state in which the wedge members 409 are in contact with the pulley 408. When the wedge members 409 are brought into contact with the pulley 408, the resulting friction can prevent sudden counterclockwise rotation of the pulley 408 caused by a load from the leaf spring 111, and thus can safely release the fastening of the wire 107. That is, it is possible to prevent the wire 107 from suddenly being loosened, and thus to allow fine adjustment. However, if the wedge members 409 are brought into contact with the pulley 408 during counterclockwise rotation of the pulley 408, the wedge members 409 are inserted deep into the gap between the pulley 408 and the polygonal piece 406, and so-called jamming may occur. If jamming occurs, it becomes difficult to move the wedge members 409 out of the gap between the pulley 408 and the polygonal piece 406. To prevent jamming, it is desirable that each groove 407 be provided with a rib or the like.

Thus, with a simple configuration, the adjusting unit 109 of the first embodiment is capable of winding the wire 107, maintaining a wound state of the wire 107 at desired positions, unwinding the wire 107, and controlling the rotation of the pulley 408 during unwinding of the wire 107.

Rotating the adjusting unit 109 clockwise allows the wearer to wind the wire 107. After winding the wire 107, when the wearer moves his/her hand off the adjusting unit 109 at a desired position, the wound state of the wire 107 can be maintained. Rotating the adjusting unit 109 counterclockwise allows the wearer to unwind the wire 107. Thus, the wearer can intuitively control the winding and unwinding of the wire 107.

In the first embodiment described above, the wire 107 is used to fasten the back head pad 104 and the top head pad 106 to the wearer's head. However, a strip-shaped member, such as a flat spiral spring, may be used as an alternative to the wire 107. In other words, the wire 107 may be replaced with any flexible member.

The polygonal piece 406 and the wedge members 409 are used in the adjusting unit 109 of the first embodiment. However, components having other shapes may be used to realize the present embodiment.

FIG. 8 is a cross-sectional view taken along line V-V of FIG. 2 to illustrate a structure of the adjusting unit 109 having alternative components. Referring to FIG. 8, a star-shaped member 801 is used as an alternative to the polygonal piece 406. At the same time, ball members 802 are used as alternatives to the wedge members 409. The biasing members 412, such as leaf springs, bias the corresponding ball members 802 clockwise. As in the case of FIG. 7, the ball members 802 are moved and inserted into narrow portions of a gap between the star-shaped member 801 and the pulley 408. Therefore, an operation similar to that in the case of FIG. 7 can be preformed.

In the first embodiment described above, the adjusting unit 109 is used to fasten the back head pad 104 and top head pad 106 of the HMD. The adjusting unit 109 may be used for applications other than the HMD.

In a second embodiment described below, the adjusting unit 109 is used as a fastening mechanism for ski boots.

FIG. 9 is a perspective view of a ski boot provided with the adjusting unit 109.

FIG. 10 is a side view of the ski boot provided with the adjusting unit 109.

Hereinafter, a ski boot provided with the adjusting unit 109 will be described with reference to FIG. 9 and FIG. 10.

A shell 901 covers a foot of a wearer of the ski boots. The shell 901 includes a toe portion 902, a heel portion 903, an ankle portion 904, an upper portion 905, and a foot insertion opening 906. It is desirable that the shell 901 be made of hard and elastic material.

A flapper 907 covers the ankle portion 904 and the upper portion 905. The flapper 907 surrounds the upper portion 905 and opens toward the front of the wearer's foot. The flapper 907 is fastened to the shell 901 by bonding, welding, or the like in an area near the Achilles' tendon.

The flapper 907 has a plurality of hooks 908 on both sides of an area open toward the front of the wearer's foot.

A wire 909 is provided for fastening the flapper 907. The wire 909 is threaded through the hooks 908 alternately from side to side. Each of the hooks 908 has a hole to allow the wire 909 to pass through. This can prevent the wire 909 from slipping off the hooks 908.

A tongue-shaped portion 910 is provided for adjusting the width of the foot insertion opening 906. The tongue-shaped portion 910 extends backward from the toe portion 902 to the ankle portion 904. The tongue-shaped portion 910 is disposed inside the flapper 907. The tongue-shaped portion 910 is fastened to the shell 901 at one end by bonding, welding, or the like in an area near the toe portion 902, but is free at the other end. Therefore, the area of the foot insertion opening 906 can be changed to fit the size of the wearer's foot. Since the inside of the tongue-shaped portion 910 is to be in direct contact with the wearer's foot, it is desirable that the tongue-shaped portion 910 be made of flexible material.

An adjusting unit 911 controls winding of the wire 909. The structure of the adjusting unit 911 is the same as that of the adjusting unit 109. The wearer rotates the adjusting unit 911 to control winding of the wire 909. The internal structure of the adjusting unit 911 is the same as that of the adjusting unit 109 illustrated in FIG. 4 and FIG. 5.

An operation of putting on the ski boot having the above-described configuration, and effects of the operation will now be described. First, when the wire 909 is loose, the tongue-shaped portion 910 is pulled forward. This increases the area of the foot insertion opening 906 of the shell 901 and allows insertion of the wearer's foot. Then, the wearer's foot is inserted into the shell 901. After the insertion, the tongue-shaped portion 910 is pulled to the inside of the flapper 907. Then, the wire 909 is wound by rotating the adjusting dial 401 of the adjusting unit 911 in CW direction shown in FIG. 9. By winding the wire 909, the flapper 907 is fastened and deformed to fit the shape of the wearer's foot. Thus, the wearer's ankle is secured.

Next, an operation performed to remove the ski boot from the wearer's foot will be described. First, the wearer rotates the adjusting dial 401 in CCW direction shown in FIG. 9. Thus, since the wedge members 409, the pulley 408, and the polygonal piece 406 inside the adjusting unit 911 are brought out of engagement, the pulley 408 having the wire 909 wound therearound becomes freely rotatable. At the same time, the flapper 907 and the tongue-shaped portion 910 around which the wire 909 is wound are released from the deformed state and restored to their initial shapes. The pulley 408 rotates until the line tension of the wire 909 becomes substantially zero. Then, by pulling the tongue-shaped portion 910 to the outside of the shell 901, the ski boot can be removed from the wearer's foot.

Thus, with a simple configuration, the second embodiment allows winding of the wire 909, locking of the wire 909 at desired positions, unlocking, and rotation control during the unlocking. Thus, it is possible to realize ski boots that are lightweight, inexpensive, and capable of providing reliable operation.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all modifications and equivalent structures and functions.

This application claims the benefit of Japanese Patent Application No. 2008-064250 filed Mar. 13, 2008, which hereby incorporated by reference herein in its entirety. 

1. A winding device comprising: a winding member configured to rotate to wind a flexible member therearound; a first rotating member configured to be rotatable; a second rotating member configured to be rotatable coaxially with the winding member, and having a smaller resistance to rotation in a predetermined direction than that to rotation in a direction opposite the predetermined direction; and an engaging member configured to bring the winding member, the first rotating member, and the second rotating member into engagement with one another when the first rotating member is subjected to a first torque, so that the winding member becomes rotatable together with the first rotating member in the predetermined direction, the engaging member being configured to release the engagement when the first rotating member is subjected to a second torque in a direction opposite that of the first torque, so that the winding member becomes rotatable in the direction opposite the predetermined direction.
 2. The winding device according to claim 1, wherein the engaging member is located between the winding member and the second rotating member.
 3. The winding device according to claim 1, wherein when the amount of rotation produced by the second torque is greater than a predetermined amount, the engaging member brings the winding member, the first rotating member, and the second rotating member into engagement with one another.
 4. The winding device according to claim 1, wherein the engaging member has a wedge shape.
 5. The winding device according to claim 1, wherein the first rotating member has a cylindrical shape.
 6. The winding device according to claim 1, wherein the engaging member is connected to the first rotating member, wherein the second rotating member has a polygonal contour, and wherein rotation of the first rotating member causes the engaging member to be inserted into a gap between the second rotating member and the winding member at positions near vertices of the polygon, so that the engaging member brings the winding member, the first rotating member, and the second rotating member into engagement with one another.
 7. The winding device according to claim 1, wherein the winding member is biased in a direction to loosen the wound flexible member, and wherein when the engagement made by the engaging member is released, the wound flexible member is loosened.
 8. The winding device according to claim 1, wherein the second rotating member increases the resistance to rotation in the direction opposite the predetermined direction, and prevents the winding member engaged with the second rotating member from rotating in the direction opposite the predetermined direction.
 9. The winding device according to claim 1, wherein the flexible member is a wire member used to fasten a mounting member of head-mounted type, and wherein rotation of the first rotating member fastens or unfastens the mounting member. 